For example, a projection screen uses a variety of optical members, such as a Fresnel lens sheet comprising an optical element for making light projected from an imaging light source follow optical paths that are approximately parallel to one another, and a lenticular lens sheet comprising an optical element for dispersing the light that have been made parallel by the Fresnel lens sheet.
In such optical members, it is necessary to prevent, as much as possible, light (imaging light) projected from an imaging light source and light (external light) emitted from an external illuminant (e.g., a lighting fixture), from being reflected from the planes of incidence and emergence of the optical members. This is because: if the surface of an optical member reflects imaging light projected from an imaging light source, a so-called ghost image (double image) is produced; and if the surface of an optical member reflects light projected from an external illuminant, image contrast is decreased.
In order to prevent such reflection of light from the surface of an optical member, a low refractive index layer has conventionally been formed as an anti-reflection layer on a part of an optical member that is required not to reflect light, such as the plane of incidence or emergence of the optical member, thereby imparting anti-reflection properties to this part. To form such a low refractive index layer, a physical vapor deposition process (PVD process), a chemical vapor deposition process (CVD process), a resin solution application process (see Japanese Laid-Open Patent Publication No. 220542/1991, for example), or the like is used.